net/mac80211/chan.c

   1 /*
   2  * mac80211 - channel management
   3  */
   4
   5 #include <linux/nl80211.h>
   6 #include <linux/export.h>
   7 #include <linux/rtnetlink.h>
   8 #include <net/cfg80211.h>
   9 #include "ieee80211_i.h"
  10 #include "driver-ops.h"
  11
  12 static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
  13                                           struct ieee80211_chanctx *ctx)
  14 {
  15         struct ieee80211_sub_if_data *sdata;
  16         int num = 0;
  17
  18         lockdep_assert_held(&local->chanctx_mtx);
  19
  20         list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
  21                 num++;
  22
  23         return num;
  24 }
  25
  26 static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
  27                                           struct ieee80211_chanctx *ctx)
  28 {
  29         struct ieee80211_sub_if_data *sdata;
  30         int num = 0;
  31
  32         lockdep_assert_held(&local->chanctx_mtx);
  33
  34         list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
  35                 num++;
  36
  37         return num;
  38 }
  39
  40 int ieee80211_chanctx_refcount(struct ieee80211_local *local,
  41                                struct ieee80211_chanctx *ctx)
  42 {
  43         return ieee80211_chanctx_num_assigned(local, ctx) +
  44                ieee80211_chanctx_num_reserved(local, ctx);
  45 }
  46
  47 static int ieee80211_num_chanctx(struct ieee80211_local *local)
  48 {
  49         struct ieee80211_chanctx *ctx;
  50         int num = 0;
  51
  52         lockdep_assert_held(&local->chanctx_mtx);
  53
  54         list_for_each_entry(ctx, &local->chanctx_list, list)
  55                 num++;
  56
  57         return num;
  58 }
  59
  60 static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
  61 {
  62         lockdep_assert_held(&local->chanctx_mtx);
  63         return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
  64 }
  65
  66 static struct ieee80211_chanctx *
  67 ieee80211_vif_get_chanctx(struct ieee80211_sub_if_data *sdata)
  68 {
  69         struct ieee80211_local *local __maybe_unused = sdata->local;
  70         struct ieee80211_chanctx_conf *conf;
  71
  72         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
  73                                          lockdep_is_held(&local->chanctx_mtx));
  74         if (!conf)
  75                 return NULL;
  76
  77         return container_of(conf, struct ieee80211_chanctx, conf);
  78 }
  79
  80 static const struct cfg80211_chan_def *
  81 ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local,
  82                                    struct ieee80211_chanctx *ctx,
  83                                    const struct cfg80211_chan_def *compat)
  84 {
  85         struct ieee80211_sub_if_data *sdata;
  86
  87         lockdep_assert_held(&local->chanctx_mtx);
  88
  89         list_for_each_entry(sdata, &ctx->reserved_vifs,
  90                             reserved_chanctx_list) {
  91                 if (!compat)
  92                         compat = &sdata->reserved_chandef;
  93
  94                 compat = cfg80211_chandef_compatible(&sdata->reserved_chandef,
  95                                                      compat);
  96                 if (!compat)
  97                         break;
  98         }
  99
 100         return compat;
 101 }
 102
 103 static const struct cfg80211_chan_def *
 104 ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
 105                                        struct ieee80211_chanctx *ctx,
 106                                        const struct cfg80211_chan_def *compat)
 107 {
 108         struct ieee80211_sub_if_data *sdata;
 109
 110         lockdep_assert_held(&local->chanctx_mtx);
 111
 112         list_for_each_entry(sdata, &ctx->assigned_vifs,
 113                             assigned_chanctx_list) {
 114                 if (sdata->reserved_chanctx != NULL)
 115                         continue;
 116
 117                 if (!compat)
 118                         compat = &sdata->vif.bss_conf.chandef;
 119
 120                 compat = cfg80211_chandef_compatible(
 121                                 &sdata->vif.bss_conf.chandef, compat);
 122                 if (!compat)
 123                         break;
 124         }
 125
 126         return compat;
 127 }
 128
 129 static const struct cfg80211_chan_def *
 130 ieee80211_chanctx_combined_chandef(struct ieee80211_local *local,
 131                                    struct ieee80211_chanctx *ctx,
 132                                    const struct cfg80211_chan_def *compat)
 133 {
 134         lockdep_assert_held(&local->chanctx_mtx);
 135
 136         compat = ieee80211_chanctx_reserved_chandef(local, ctx, compat);
 137         if (!compat)
 138                 return NULL;
 139
 140         compat = ieee80211_chanctx_non_reserved_chandef(local, ctx, compat);
 141         if (!compat)
 142                 return NULL;
 143
 144         return compat;
 145 }
 146
 147 static bool
 148 ieee80211_chanctx_can_reserve_chandef(struct ieee80211_local *local,
 149                                       struct ieee80211_chanctx *ctx,
 150                                       const struct cfg80211_chan_def *def)
 151 {
 152         lockdep_assert_held(&local->chanctx_mtx);
 153
 154         if (ieee80211_chanctx_combined_chandef(local, ctx, def))
 155                 return true;
 156
 157         if (!list_empty(&ctx->reserved_vifs) &&
 158             ieee80211_chanctx_reserved_chandef(local, ctx, def))
 159                 return true;
 160
 161         return false;
 162 }
 163
 164 static struct ieee80211_chanctx *
 165 ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
 166                                    const struct cfg80211_chan_def *chandef,
 167                                    enum ieee80211_chanctx_mode mode)
 168 {
 169         struct ieee80211_chanctx *ctx;
 170
 171         lockdep_assert_held(&local->chanctx_mtx);
 172
 173         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 174                 return NULL;
 175
 176         list_for_each_entry(ctx, &local->chanctx_list, list) {
 177                 if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
 178                         continue;
 179
 180                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 181                         continue;
 182
 183                 if (!ieee80211_chanctx_can_reserve_chandef(local, ctx,
 184                                                            chandef))
 185                         continue;
 186
 187                 return ctx;
 188         }
 189
 190         return NULL;
 191 }
 192
 193 static enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
 194 {
 195         switch (sta->bandwidth) {
 196         case IEEE80211_STA_RX_BW_20:
 197                 if (sta->ht_cap.ht_supported)
 198                         return NL80211_CHAN_WIDTH_20;
 199                 else
 200                         return NL80211_CHAN_WIDTH_20_NOHT;
 201         case IEEE80211_STA_RX_BW_40:
 202                 return NL80211_CHAN_WIDTH_40;
 203         case IEEE80211_STA_RX_BW_80:
 204                 return NL80211_CHAN_WIDTH_80;
 205         case IEEE80211_STA_RX_BW_160:
 206                 /*
 207                  * This applied for both 160 and 80+80. since we use
 208                  * the returned value to consider degradation of
 209                  * ctx->conf.min_def, we have to make sure to take
 210                  * the bigger one (NL80211_CHAN_WIDTH_160).
 211                  * Otherwise we might try degrading even when not
 212                  * needed, as the max required sta_bw returned (80+80)
 213                  * might be smaller than the configured bw (160).
 214                  */
 215                 return NL80211_CHAN_WIDTH_160;
 216         default:
 217                 WARN_ON(1);
 218                 return NL80211_CHAN_WIDTH_20;
 219         }
 220 }
 221
 222 static enum nl80211_chan_width
 223 ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
 224 {
 225         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 226         struct sta_info *sta;
 227
 228         rcu_read_lock();
 229         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
 230                 if (sdata != sta->sdata &&
 231                     !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
 232                         continue;
 233
 234                 if (!sta->uploaded)
 235                         continue;
 236
 237                 max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
 238         }
 239         rcu_read_unlock();
 240
 241         return max_bw;
 242 }
 243
 244 static enum nl80211_chan_width
 245 ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
 246                                       struct ieee80211_chanctx_conf *conf)
 247 {
 248         struct ieee80211_sub_if_data *sdata;
 249         enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
 250
 251         rcu_read_lock();
 252         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 253                 struct ieee80211_vif *vif = &sdata->vif;
 254                 enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;
 255
 256                 if (!ieee80211_sdata_running(sdata))
 257                         continue;
 258
 259                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 260                         continue;
 261
 262                 switch (vif->type) {
 263                 case NL80211_IFTYPE_AP:
 264                 case NL80211_IFTYPE_AP_VLAN:
 265                         width = ieee80211_get_max_required_bw(sdata);
 266                         break;
 267                 case NL80211_IFTYPE_P2P_DEVICE:
 268                         continue;
 269                 case NL80211_IFTYPE_STATION:
 270                 case NL80211_IFTYPE_ADHOC:
 271                 case NL80211_IFTYPE_WDS:
 272                 case NL80211_IFTYPE_MESH_POINT:
 273                 case NL80211_IFTYPE_OCB:
 274                         width = vif->bss_conf.chandef.width;
 275                         break;
 276                 case NL80211_IFTYPE_UNSPECIFIED:
 277                 case NUM_NL80211_IFTYPES:
 278                 case NL80211_IFTYPE_MONITOR:
 279                 case NL80211_IFTYPE_P2P_CLIENT:
 280                 case NL80211_IFTYPE_P2P_GO:
 281                         WARN_ON_ONCE(1);
 282                 }
 283                 max_bw = max(max_bw, width);
 284         }
 285
 286         /* use the configured bandwidth in case of monitor interface */
 287         sdata = rcu_dereference(local->monitor_sdata);
 288         if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
 289                 max_bw = max(max_bw, conf->def.width);
 290
 291         rcu_read_unlock();
 292
 293         return max_bw;
 294 }
 295
 296 /*
 297  * recalc the min required chan width of the channel context, which is
 298  * the max of min required widths of all the interfaces bound to this
 299  * channel context.
 300  */
 301 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
 302                                       struct ieee80211_chanctx *ctx)
 303 {
 304         enum nl80211_chan_width max_bw;
 305         struct cfg80211_chan_def min_def;
 306
 307         lockdep_assert_held(&local->chanctx_mtx);
 308
 309         /* don't optimize 5MHz, 10MHz, and radar_enabled confs */
 310         if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
 311             ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
 312             ctx->conf.radar_enabled) {
 313                 ctx->conf.min_def = ctx->conf.def;
 314                 return;
 315         }
 316
 317         max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
 318
 319         /* downgrade chandef up to max_bw */
 320         min_def = ctx->conf.def;
 321         while (min_def.width > max_bw)
 322                 ieee80211_chandef_downgrade(&min_def);
 323
 324         if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
 325                 return;
 326
 327         ctx->conf.min_def = min_def;
 328         if (!ctx->driver_present)
 329                 return;
 330
 331         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
 332 }
 333
 334 static void ieee80211_change_chanctx(struct ieee80211_local *local,
 335                                      struct ieee80211_chanctx *ctx,
 336                                      const struct cfg80211_chan_def *chandef)
 337 {
 338         if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
 339                 return;
 340
 341         WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
 342
 343         ctx->conf.def = *chandef;
 344         drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
 345         ieee80211_recalc_chanctx_min_def(local, ctx);
 346
 347         if (!local->use_chanctx) {
 348                 local->_oper_chandef = *chandef;
 349                 ieee80211_hw_config(local, 0);
 350         }
 351 }
 352
 353 static struct ieee80211_chanctx *
 354 ieee80211_find_chanctx(struct ieee80211_local *local,
 355                        const struct cfg80211_chan_def *chandef,
 356                        enum ieee80211_chanctx_mode mode)
 357 {
 358         struct ieee80211_chanctx *ctx;
 359
 360         lockdep_assert_held(&local->chanctx_mtx);
 361
 362         if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
 363                 return NULL;
 364
 365         list_for_each_entry(ctx, &local->chanctx_list, list) {
 366                 const struct cfg80211_chan_def *compat;
 367
 368                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
 369                         continue;
 370
 371                 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
 372                         continue;
 373
 374                 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
 375                 if (!compat)
 376                         continue;
 377
 378                 compat = ieee80211_chanctx_reserved_chandef(local, ctx,
 379                                                             compat);
 380                 if (!compat)
 381                         continue;
 382
 383                 ieee80211_change_chanctx(local, ctx, compat);
 384
 385                 return ctx;
 386         }
 387
 388         return NULL;
 389 }
 390
 391 bool ieee80211_is_radar_required(struct ieee80211_local *local)
 392 {
 393         struct ieee80211_sub_if_data *sdata;
 394
 395         lockdep_assert_held(&local->mtx);
 396
 397         rcu_read_lock();
 398         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 399                 if (sdata->radar_required) {
 400                         rcu_read_unlock();
 401                         return true;
 402                 }
 403         }
 404         rcu_read_unlock();
 405
 406         return false;
 407 }
 408
 409 static bool
 410 ieee80211_chanctx_radar_required(struct ieee80211_local *local,
 411                                  struct ieee80211_chanctx *ctx)
 412 {
 413         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 414         struct ieee80211_sub_if_data *sdata;
 415         bool required = false;
 416
 417         lockdep_assert_held(&local->chanctx_mtx);
 418         lockdep_assert_held(&local->mtx);
 419
 420         rcu_read_lock();
 421         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 422                 if (!ieee80211_sdata_running(sdata))
 423                         continue;
 424                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 425                         continue;
 426                 if (!sdata->radar_required)
 427                         continue;
 428
 429                 required = true;
 430                 break;
 431         }
 432         rcu_read_unlock();
 433
 434         return required;
 435 }
 436
 437 static struct ieee80211_chanctx *
 438 ieee80211_alloc_chanctx(struct ieee80211_local *local,
 439                         const struct cfg80211_chan_def *chandef,
 440                         enum ieee80211_chanctx_mode mode)
 441 {
 442         struct ieee80211_chanctx *ctx;
 443
 444         lockdep_assert_held(&local->chanctx_mtx);
 445
 446         ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
 447         if (!ctx)
 448                 return NULL;
 449
 450         INIT_LIST_HEAD(&ctx->assigned_vifs);
 451         INIT_LIST_HEAD(&ctx->reserved_vifs);
 452         ctx->conf.def = *chandef;
 453         ctx->conf.rx_chains_static = 1;
 454         ctx->conf.rx_chains_dynamic = 1;
 455         ctx->mode = mode;
 456         ctx->conf.radar_enabled = false;
 457         ieee80211_recalc_chanctx_min_def(local, ctx);
 458
 459         return ctx;
 460 }
 461
 462 static int ieee80211_add_chanctx(struct ieee80211_local *local,
 463                                  struct ieee80211_chanctx *ctx)
 464 {
 465         u32 changed;
 466         int err;
 467
 468         lockdep_assert_held(&local->mtx);
 469         lockdep_assert_held(&local->chanctx_mtx);
 470
 471         if (!local->use_chanctx)
 472                 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
 473
 474         /* turn idle off *before* setting channel -- some drivers need that */
 475         changed = ieee80211_idle_off(local);
 476         if (changed)
 477                 ieee80211_hw_config(local, changed);
 478
 479         if (!local->use_chanctx) {
 480                 local->_oper_chandef = ctx->conf.def;
 481                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 482         } else {
 483                 err = drv_add_chanctx(local, ctx);
 484                 if (err) {
 485                         ieee80211_recalc_idle(local);
 486                         return err;
 487                 }
 488         }
 489
 490         return 0;
 491 }
 492
 493 static struct ieee80211_chanctx *
 494 ieee80211_new_chanctx(struct ieee80211_local *local,
 495                       const struct cfg80211_chan_def *chandef,
 496                       enum ieee80211_chanctx_mode mode)
 497 {
 498         struct ieee80211_chanctx *ctx;
 499         int err;
 500
 501         lockdep_assert_held(&local->mtx);
 502         lockdep_assert_held(&local->chanctx_mtx);
 503
 504         ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 505         if (!ctx)
 506                 return ERR_PTR(-ENOMEM);
 507
 508         err = ieee80211_add_chanctx(local, ctx);
 509         if (err) {
 510                 kfree(ctx);
 511                 return ERR_PTR(err);
 512         }
 513
 514         list_add_rcu(&ctx->list, &local->chanctx_list);
 515         return ctx;
 516 }
 517
 518 static void ieee80211_del_chanctx(struct ieee80211_local *local,
 519                                   struct ieee80211_chanctx *ctx)
 520 {
 521         lockdep_assert_held(&local->chanctx_mtx);
 522
 523         if (!local->use_chanctx) {
 524                 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
 525                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 526                 chandef->center_freq1 = chandef->chan->center_freq;
 527                 chandef->center_freq2 = 0;
 528
 529                 /* NOTE: Disabling radar is only valid here for
 530                  * single channel context. To be sure, check it ...
 531                  */
 532                 WARN_ON(local->hw.conf.radar_enabled &&
 533                         !list_empty(&local->chanctx_list));
 534
 535                 local->hw.conf.radar_enabled = false;
 536
 537                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 538         } else {
 539                 drv_remove_chanctx(local, ctx);
 540         }
 541
 542         ieee80211_recalc_idle(local);
 543 }
 544
 545 static void ieee80211_free_chanctx(struct ieee80211_local *local,
 546                                    struct ieee80211_chanctx *ctx)
 547 {
 548         lockdep_assert_held(&local->chanctx_mtx);
 549
 550         WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
 551
 552         list_del_rcu(&ctx->list);
 553         ieee80211_del_chanctx(local, ctx);
 554         kfree_rcu(ctx, rcu_head);
 555 }
 556
 557 static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
 558                                               struct ieee80211_chanctx *ctx)
 559 {
 560         struct ieee80211_chanctx_conf *conf = &ctx->conf;
 561         struct ieee80211_sub_if_data *sdata;
 562         const struct cfg80211_chan_def *compat = NULL;
 563
 564         lockdep_assert_held(&local->chanctx_mtx);
 565
 566         rcu_read_lock();
 567         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 568
 569                 if (!ieee80211_sdata_running(sdata))
 570                         continue;
 571                 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
 572                         continue;
 573                 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 574                         continue;
 575
 576                 if (!compat)
 577                         compat = &sdata->vif.bss_conf.chandef;
 578
 579                 compat = cfg80211_chandef_compatible(
 580                                 &sdata->vif.bss_conf.chandef, compat);
 581                 if (WARN_ON_ONCE(!compat))
 582                         break;
 583         }
 584         rcu_read_unlock();
 585
 586         if (!compat)
 587                 return;
 588
 589         ieee80211_change_chanctx(local, ctx, compat);
 590 }
 591
 592 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
 593                                            struct ieee80211_chanctx *chanctx)
 594 {
 595         bool radar_enabled;
 596
 597         lockdep_assert_held(&local->chanctx_mtx);
 598         /* for ieee80211_is_radar_required */
 599         lockdep_assert_held(&local->mtx);
 600
 601         radar_enabled = ieee80211_chanctx_radar_required(local, chanctx);
 602
 603         if (radar_enabled == chanctx->conf.radar_enabled)
 604                 return;
 605
 606         chanctx->conf.radar_enabled = radar_enabled;
 607
 608         if (!local->use_chanctx) {
 609                 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
 610                 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 611         }
 612
 613         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
 614 }
 615
 616 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 617                                         struct ieee80211_chanctx *new_ctx)
 618 {
 619         struct ieee80211_local *local = sdata->local;
 620         struct ieee80211_chanctx_conf *conf;
 621         struct ieee80211_chanctx *curr_ctx = NULL;
 622         int ret = 0;
 623
 624         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 625                                          lockdep_is_held(&local->chanctx_mtx));
 626
 627         if (conf) {
 628                 curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
 629
 630                 drv_unassign_vif_chanctx(local, sdata, curr_ctx);
 631                 conf = NULL;
 632                 list_del(&sdata->assigned_chanctx_list);
 633         }
 634
 635         if (new_ctx) {
 636                 ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
 637                 if (ret)
 638                         goto out;
 639
 640                 conf = &new_ctx->conf;
 641                 list_add(&sdata->assigned_chanctx_list,
 642                          &new_ctx->assigned_vifs);
 643         }
 644
 645 out:
 646         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
 647
 648         sdata->vif.bss_conf.idle = !conf;
 649
 650         if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
 651                 ieee80211_recalc_chanctx_chantype(local, curr_ctx);
 652                 ieee80211_recalc_smps_chanctx(local, curr_ctx);
 653                 ieee80211_recalc_radar_chanctx(local, curr_ctx);
 654                 ieee80211_recalc_chanctx_min_def(local, curr_ctx);
 655         }
 656
 657         if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
 658                 ieee80211_recalc_txpower(sdata, false);
 659                 ieee80211_recalc_chanctx_min_def(local, new_ctx);
 660         }
 661
 662         if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
 663             sdata->vif.type != NL80211_IFTYPE_MONITOR)
 664                 ieee80211_bss_info_change_notify(sdata,
 665                                                  BSS_CHANGED_IDLE);
 666
 667         ieee80211_check_fast_xmit_iface(sdata);
 668
 669         return ret;
 670 }
 671
 672 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
 673                                    struct ieee80211_chanctx *chanctx)
 674 {
 675         struct ieee80211_sub_if_data *sdata;
 676         u8 rx_chains_static, rx_chains_dynamic;
 677
 678         lockdep_assert_held(&local->chanctx_mtx);
 679
 680         rx_chains_static = 1;
 681         rx_chains_dynamic = 1;
 682
 683         rcu_read_lock();
 684         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 685                 u8 needed_static, needed_dynamic;
 686
 687                 if (!ieee80211_sdata_running(sdata))
 688                         continue;
 689
 690                 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
 691                                                 &chanctx->conf)
 692                         continue;
 693
 694                 switch (sdata->vif.type) {
 695                 case NL80211_IFTYPE_P2P_DEVICE:
 696                         continue;
 697                 case NL80211_IFTYPE_STATION:
 698                         if (!sdata->u.mgd.associated)
 699                                 continue;
 700                         break;
 701                 case NL80211_IFTYPE_AP_VLAN:
 702                         continue;
 703                 case NL80211_IFTYPE_AP:
 704                 case NL80211_IFTYPE_ADHOC:
 705                 case NL80211_IFTYPE_WDS:
 706                 case NL80211_IFTYPE_MESH_POINT:
 707                 case NL80211_IFTYPE_OCB:
 708                         break;
 709                 default:
 710                         WARN_ON_ONCE(1);
 711                 }
 712
 713                 switch (sdata->smps_mode) {
 714                 default:
 715                         WARN_ONCE(1, "Invalid SMPS mode %d\n",
 716                                   sdata->smps_mode);
 717                         /* fall through */
 718                 case IEEE80211_SMPS_OFF:
 719                         needed_static = sdata->needed_rx_chains;
 720                         needed_dynamic = sdata->needed_rx_chains;
 721                         break;
 722                 case IEEE80211_SMPS_DYNAMIC:
 723                         needed_static = 1;
 724                         needed_dynamic = sdata->needed_rx_chains;
 725                         break;
 726                 case IEEE80211_SMPS_STATIC:
 727                         needed_static = 1;
 728                         needed_dynamic = 1;
 729                         break;
 730                 }
 731
 732                 rx_chains_static = max(rx_chains_static, needed_static);
 733                 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
 734         }
 735
 736         /* Disable SMPS for the monitor interface */
 737         sdata = rcu_dereference(local->monitor_sdata);
 738         if (sdata &&
 739             rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
 740                 rx_chains_dynamic = rx_chains_static = local->rx_chains;
 741
 742         rcu_read_unlock();
 743
 744         if (!local->use_chanctx) {
 745                 if (rx_chains_static > 1)
 746                         local->smps_mode = IEEE80211_SMPS_OFF;
 747                 else if (rx_chains_dynamic > 1)
 748                         local->smps_mode = IEEE80211_SMPS_DYNAMIC;
 749                 else
 750                         local->smps_mode = IEEE80211_SMPS_STATIC;
 751                 ieee80211_hw_config(local, 0);
 752         }
 753
 754         if (rx_chains_static == chanctx->conf.rx_chains_static &&
 755             rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
 756                 return;
 757
 758         chanctx->conf.rx_chains_static = rx_chains_static;
 759         chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
 760         drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
 761 }
 762
 763 static void
 764 __ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 765                                       bool clear)
 766 {
 767         struct ieee80211_local *local __maybe_unused = sdata->local;
 768         struct ieee80211_sub_if_data *vlan;
 769         struct ieee80211_chanctx_conf *conf;
 770
 771         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
 772                 return;
 773
 774         lockdep_assert_held(&local->mtx);
 775
 776         /* Check that conf exists, even when clearing this function
 777          * must be called with the AP's channel context still there
 778          * as it would otherwise cause VLANs to have an invalid
 779          * channel context pointer for a while, possibly pointing
 780          * to a channel context that has already been freed.
 781          */
 782         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
 783                                          lockdep_is_held(&local->chanctx_mtx));
 784         WARN_ON(!conf);
 785
 786         if (clear)
 787                 conf = NULL;
 788
 789         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 790                 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
 791 }
 792
 793 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
 794                                          bool clear)
 795 {
 796         struct ieee80211_local *local = sdata->local;
 797
 798         mutex_lock(&local->chanctx_mtx);
 799
 800         __ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);
 801
 802         mutex_unlock(&local->chanctx_mtx);
 803 }
 804
 805 int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
 806 {
 807         struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;
 808
 809         lockdep_assert_held(&sdata->local->chanctx_mtx);
 810
 811         if (WARN_ON(!ctx))
 812                 return -EINVAL;
 813
 814         list_del(&sdata->reserved_chanctx_list);
 815         sdata->reserved_chanctx = NULL;
 816
 817         if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
 818                 if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
 819                         if (WARN_ON(!ctx->replace_ctx))
 820                                 return -EINVAL;
 821
 822                         WARN_ON(ctx->replace_ctx->replace_state !=
 823                                 IEEE80211_CHANCTX_WILL_BE_REPLACED);
 824                         WARN_ON(ctx->replace_ctx->replace_ctx != ctx);
 825
 826                         ctx->replace_ctx->replace_ctx = NULL;
 827                         ctx->replace_ctx->replace_state =
 828                                         IEEE80211_CHANCTX_REPLACE_NONE;
 829
 830                         list_del_rcu(&ctx->list);
 831                         kfree_rcu(ctx, rcu_head);
 832                 } else {
 833                         ieee80211_free_chanctx(sdata->local, ctx);
 834                 }
 835         }
 836
 837         return 0;
 838 }
 839
 840 int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
 841                                   const struct cfg80211_chan_def *chandef,
 842                                   enum ieee80211_chanctx_mode mode,
 843                                   bool radar_required)
 844 {
 845         struct ieee80211_local *local = sdata->local;
 846         struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
 847
 848         lockdep_assert_held(&local->chanctx_mtx);
 849
 850         curr_ctx = ieee80211_vif_get_chanctx(sdata);
 851         if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
 852                 return -ENOTSUPP;
 853
 854         new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
 855         if (!new_ctx) {
 856                 if (ieee80211_can_create_new_chanctx(local)) {
 857                         new_ctx = ieee80211_new_chanctx(local, chandef, mode);
 858                         if (IS_ERR(new_ctx))
 859                                 return PTR_ERR(new_ctx);
 860                 } else {
 861                         if (!curr_ctx ||
 862                             (curr_ctx->replace_state ==
 863                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 864                             !list_empty(&curr_ctx->reserved_vifs)) {
 865                                 /*
 866                                  * Another vif already requested this context
 867                                  * for a reservation. Find another one hoping
 868                                  * all vifs assigned to it will also switch
 869                                  * soon enough.
 870                                  *
 871                                  * TODO: This needs a little more work as some
 872                                  * cases (more than 2 chanctx capable devices)
 873                                  * may fail which could otherwise succeed
 874                                  * provided some channel context juggling was
 875                                  * performed.
 876                                  *
 877                                  * Consider ctx1..3, vif1..6, each ctx has 2
 878                                  * vifs. vif1 and vif2 from ctx1 request new
 879                                  * different chandefs starting 2 in-place
 880                                  * reserations with ctx4 and ctx5 replacing
 881                                  * ctx1 and ctx2 respectively. Next vif5 and
 882                                  * vif6 from ctx3 reserve ctx4. If vif3 and
 883                                  * vif4 remain on ctx2 as they are then this
 884                                  * fails unless `replace_ctx` from ctx5 is
 885                                  * replaced with ctx3.
 886                                  */
 887                                 list_for_each_entry(ctx, &local->chanctx_list,
 888                                                     list) {
 889                                         if (ctx->replace_state !=
 890                                             IEEE80211_CHANCTX_REPLACE_NONE)
 891                                                 continue;
 892
 893                                         if (!list_empty(&ctx->reserved_vifs))
 894                                                 continue;
 895
 896                                         curr_ctx = ctx;
 897                                         break;
 898                                 }
 899                         }
 900
 901                         /*
 902                          * If that's true then all available contexts already
 903                          * have reservations and cannot be used.
 904                          */
 905                         if (!curr_ctx ||
 906                             (curr_ctx->replace_state ==
 907                              IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 908                             !list_empty(&curr_ctx->reserved_vifs))
 909                                 return -EBUSY;
 910
 911                         new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
 912                         if (!new_ctx)
 913                                 return -ENOMEM;
 914
 915                         new_ctx->replace_ctx = curr_ctx;
 916                         new_ctx->replace_state =
 917                                         IEEE80211_CHANCTX_REPLACES_OTHER;
 918
 919                         curr_ctx->replace_ctx = new_ctx;
 920                         curr_ctx->replace_state =
 921                                         IEEE80211_CHANCTX_WILL_BE_REPLACED;
 922
 923                         list_add_rcu(&new_ctx->list, &local->chanctx_list);
 924                 }
 925         }
 926
 927         list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
 928         sdata->reserved_chanctx = new_ctx;
 929         sdata->reserved_chandef = *chandef;
 930         sdata->reserved_radar_required = radar_required;
 931         sdata->reserved_ready = false;
 932
 933         return 0;
 934 }
 935
 936 static void
 937 ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
 938 {
 939         switch (sdata->vif.type) {
 940         case NL80211_IFTYPE_ADHOC:
 941         case NL80211_IFTYPE_AP:
 942         case NL80211_IFTYPE_MESH_POINT:
 943         case NL80211_IFTYPE_OCB:
 944                 ieee80211_queue_work(&sdata->local->hw,
 945                                      &sdata->csa_finalize_work);
 946                 break;
 947         case NL80211_IFTYPE_STATION:
 948                 ieee80211_queue_work(&sdata->local->hw,
 949                                      &sdata->u.mgd.chswitch_work);
 950                 break;
 951         case NL80211_IFTYPE_UNSPECIFIED:
 952         case NL80211_IFTYPE_AP_VLAN:
 953         case NL80211_IFTYPE_WDS:
 954         case NL80211_IFTYPE_MONITOR:
 955         case NL80211_IFTYPE_P2P_CLIENT:
 956         case NL80211_IFTYPE_P2P_GO:
 957         case NL80211_IFTYPE_P2P_DEVICE:
 958         case NUM_NL80211_IFTYPES:
 959                 WARN_ON(1);
 960                 break;
 961         }
 962 }
 963
 964 static void
 965 ieee80211_vif_update_chandef(struct ieee80211_sub_if_data *sdata,
 966                              const struct cfg80211_chan_def *chandef)
 967 {
 968         struct ieee80211_sub_if_data *vlan;
 969
 970         sdata->vif.bss_conf.chandef = *chandef;
 971
 972         if (sdata->vif.type != NL80211_IFTYPE_AP)
 973                 return;
 974
 975         list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 976                 vlan->vif.bss_conf.chandef = *chandef;
 977 }
 978
 979 static int
 980 ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
 981 {
 982         struct ieee80211_local *local = sdata->local;
 983         struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
 984         struct ieee80211_chanctx *old_ctx, *new_ctx;
 985         const struct cfg80211_chan_def *chandef;
 986         u32 changed = 0;
 987         int err;
 988
 989         lockdep_assert_held(&local->mtx);
 990         lockdep_assert_held(&local->chanctx_mtx);
 991
 992         new_ctx = sdata->reserved_chanctx;
 993         old_ctx = ieee80211_vif_get_chanctx(sdata);
 994
 995         if (WARN_ON(!sdata->reserved_ready))
 996                 return -EBUSY;
 997
 998         if (WARN_ON(!new_ctx))
 999                 return -EINVAL;
1000
1001         if (WARN_ON(!old_ctx))
1002                 return -EINVAL;
1003
1004         if (WARN_ON(new_ctx->replace_state ==
1005                     IEEE80211_CHANCTX_REPLACES_OTHER))
1006                 return -EINVAL;
1007
1008         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1009                                 &sdata->reserved_chandef);
1010         if (WARN_ON(!chandef))
1011                 return -EINVAL;
1012
1013         ieee80211_change_chanctx(local, new_ctx, chandef);
1014
1015         vif_chsw[0].vif = &sdata->vif;
1016         vif_chsw[0].old_ctx = &old_ctx->conf;
1017         vif_chsw[0].new_ctx = &new_ctx->conf;
1018
1019         list_del(&sdata->reserved_chanctx_list);
1020         sdata->reserved_chanctx = NULL;
1021
1022         err = drv_switch_vif_chanctx(local, vif_chsw, 1,
1023                                      CHANCTX_SWMODE_REASSIGN_VIF);
1024         if (err) {
1025                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1026                         ieee80211_free_chanctx(local, new_ctx);
1027
1028                 goto out;
1029         }
1030
1031         list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
1032         rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);
1033
1034         if (sdata->vif.type == NL80211_IFTYPE_AP)
1035                 __ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
1036
1037         ieee80211_check_fast_xmit_iface(sdata);
1038
1039         if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
1040                 ieee80211_free_chanctx(local, old_ctx);
1041
1042         if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1043                 changed = BSS_CHANGED_BANDWIDTH;
1044
1045         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1046
1047         ieee80211_recalc_smps_chanctx(local, new_ctx);
1048         ieee80211_recalc_radar_chanctx(local, new_ctx);
1049         ieee80211_recalc_chanctx_min_def(local, new_ctx);
1050
1051         if (changed)
1052                 ieee80211_bss_info_change_notify(sdata, changed);
1053
1054 out:
1055         ieee80211_vif_chanctx_reservation_complete(sdata);
1056         return err;
1057 }
1058
1059 static int
1060 ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
1061 {
1062         struct ieee80211_local *local = sdata->local;
1063         struct ieee80211_chanctx *old_ctx, *new_ctx;
1064         const struct cfg80211_chan_def *chandef;
1065         int err;
1066
1067         old_ctx = ieee80211_vif_get_chanctx(sdata);
1068         new_ctx = sdata->reserved_chanctx;
1069
1070         if (WARN_ON(!sdata->reserved_ready))
1071                 return -EINVAL;
1072
1073         if (WARN_ON(old_ctx))
1074                 return -EINVAL;
1075
1076         if (WARN_ON(!new_ctx))
1077                 return -EINVAL;
1078
1079         if (WARN_ON(new_ctx->replace_state ==
1080                     IEEE80211_CHANCTX_REPLACES_OTHER))
1081                 return -EINVAL;
1082
1083         chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
1084                                 &sdata->reserved_chandef);
1085         if (WARN_ON(!chandef))
1086                 return -EINVAL;
1087
1088         ieee80211_change_chanctx(local, new_ctx, chandef);
1089
1090         list_del(&sdata->reserved_chanctx_list);
1091         sdata->reserved_chanctx = NULL;
1092
1093         err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
1094         if (err) {
1095                 if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
1096                         ieee80211_free_chanctx(local, new_ctx);
1097
1098                 goto out;
1099         }
1100
1101 out:
1102         ieee80211_vif_chanctx_reservation_complete(sdata);
1103         return err;
1104 }
1105
1106 static bool
1107 ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
1108 {
1109         struct ieee80211_chanctx *old_ctx, *new_ctx;
1110
1111         lockdep_assert_held(&sdata->local->chanctx_mtx);
1112
1113         new_ctx = sdata->reserved_chanctx;
1114         old_ctx = ieee80211_vif_get_chanctx(sdata);
1115
1116         if (!old_ctx)
1117                 return false;
1118
1119         if (WARN_ON(!new_ctx))
1120                 return false;
1121
1122         if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1123                 return false;
1124
1125         if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1126                 return false;
1127
1128         return true;
1129 }
1130
1131 static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
1132                                         struct ieee80211_chanctx *new_ctx)
1133 {
1134         const struct cfg80211_chan_def *chandef;
1135
1136         lockdep_assert_held(&local->mtx);
1137         lockdep_assert_held(&local->chanctx_mtx);
1138
1139         chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
1140         if (WARN_ON(!chandef))
1141                 return -EINVAL;
1142
1143         local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
1144         local->_oper_chandef = *chandef;
1145         ieee80211_hw_config(local, 0);
1146
1147         return 0;
1148 }
1149
1150 static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
1151                                       int n_vifs)
1152 {
1153         struct ieee80211_vif_chanctx_switch *vif_chsw;
1154         struct ieee80211_sub_if_data *sdata;
1155         struct ieee80211_chanctx *ctx, *old_ctx;
1156         int i, err;
1157
1158         lockdep_assert_held(&local->mtx);
1159         lockdep_assert_held(&local->chanctx_mtx);
1160
1161         vif_chsw = kzalloc(sizeof(vif_chsw[0]) * n_vifs, GFP_KERNEL);
1162         if (!vif_chsw)
1163                 return -ENOMEM;
1164
1165         i = 0;
1166         list_for_each_entry(ctx, &local->chanctx_list, list) {
1167                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1168                         continue;
1169
1170                 if (WARN_ON(!ctx->replace_ctx)) {
1171                         err = -EINVAL;
1172                         goto out;
1173                 }
1174
1175                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1176                                     reserved_chanctx_list) {
1177                         if (!ieee80211_vif_has_in_place_reservation(
1178                                         sdata))
1179                                 continue;
1180
1181                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1182                         vif_chsw[i].vif = &sdata->vif;
1183                         vif_chsw[i].old_ctx = &old_ctx->conf;
1184                         vif_chsw[i].new_ctx = &ctx->conf;
1185
1186                         i++;
1187                 }
1188         }
1189
1190         err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
1191                                      CHANCTX_SWMODE_SWAP_CONTEXTS);
1192
1193 out:
1194         kfree(vif_chsw);
1195         return err;
1196 }
1197
1198 static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
1199 {
1200         struct ieee80211_chanctx *ctx;
1201         int err;
1202
1203         lockdep_assert_held(&local->mtx);
1204         lockdep_assert_held(&local->chanctx_mtx);
1205
1206         list_for_each_entry(ctx, &local->chanctx_list, list) {
1207                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1208                         continue;
1209
1210                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1211                         continue;
1212
1213                 ieee80211_del_chanctx(local, ctx->replace_ctx);
1214                 err = ieee80211_add_chanctx(local, ctx);
1215                 if (err)
1216                         goto err;
1217         }
1218
1219         return 0;
1220
1221 err:
1222         WARN_ON(ieee80211_add_chanctx(local, ctx));
1223         list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
1224                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1225                         continue;
1226
1227                 if (!list_empty(&ctx->replace_ctx->assigned_vifs))
1228                         continue;
1229
1230                 ieee80211_del_chanctx(local, ctx);
1231                 WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
1232         }
1233
1234         return err;
1235 }
1236
1237 static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
1238 {
1239         struct ieee80211_sub_if_data *sdata, *sdata_tmp;
1240         struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
1241         struct ieee80211_chanctx *new_ctx = NULL;
1242         int i, err, n_assigned, n_reserved, n_ready;
1243         int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;
1244
1245         lockdep_assert_held(&local->mtx);
1246         lockdep_assert_held(&local->chanctx_mtx);
1247
1248         /*
1249          * If there are 2 independent pairs of channel contexts performing
1250          * cross-switch of their vifs this code will still wait until both are
1251          * ready even though it could be possible to switch one before the
1252          * other is ready.
1253          *
1254          * For practical reasons and code simplicity just do a single huge
1255          * switch.
1256          */
1257
1258         /*
1259          * Verify if the reservation is still feasible.
1260          *  - if it's not then disconnect
1261          *  - if it is but not all vifs necessary are ready then defer
1262          */
1263
1264         list_for_each_entry(ctx, &local->chanctx_list, list) {
1265                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1266                         continue;
1267
1268                 if (WARN_ON(!ctx->replace_ctx)) {
1269                         err = -EINVAL;
1270                         goto err;
1271                 }
1272
1273                 if (!local->use_chanctx)
1274                         new_ctx = ctx;
1275
1276                 n_ctx++;
1277
1278                 n_assigned = 0;
1279                 n_reserved = 0;
1280                 n_ready = 0;
1281
1282                 list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
1283                                     assigned_chanctx_list) {
1284                         n_assigned++;
1285                         if (sdata->reserved_chanctx) {
1286                                 n_reserved++;
1287                                 if (sdata->reserved_ready)
1288                                         n_ready++;
1289                         }
1290                 }
1291
1292                 if (n_assigned != n_reserved) {
1293                         if (n_ready == n_reserved) {
1294                                 wiphy_info(local->hw.wiphy,
1295                                            "channel context reservation cannot be finalized because some interfaces aren't switching\n");
1296                                 err = -EBUSY;
1297                                 goto err;
1298                         }
1299
1300                         return -EAGAIN;
1301                 }
1302
1303                 ctx->conf.radar_enabled = false;
1304                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1305                                     reserved_chanctx_list) {
1306                         if (ieee80211_vif_has_in_place_reservation(sdata) &&
1307                             !sdata->reserved_ready)
1308                                 return -EAGAIN;
1309
1310                         old_ctx = ieee80211_vif_get_chanctx(sdata);
1311                         if (old_ctx) {
1312                                 if (old_ctx->replace_state ==
1313                                     IEEE80211_CHANCTX_WILL_BE_REPLACED)
1314                                         n_vifs_switch++;
1315                                 else
1316                                         n_vifs_assign++;
1317                         } else {
1318                                 n_vifs_ctxless++;
1319                         }
1320
1321                         if (sdata->reserved_radar_required)
1322                                 ctx->conf.radar_enabled = true;
1323                 }
1324         }
1325
1326         if (WARN_ON(n_ctx == 0) ||
1327             WARN_ON(n_vifs_switch == 0 &&
1328                     n_vifs_assign == 0 &&
1329                     n_vifs_ctxless == 0) ||
1330             WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
1331             WARN_ON(!new_ctx && !local->use_chanctx)) {
1332                 err = -EINVAL;
1333                 goto err;
1334         }
1335
1336         /*
1337          * All necessary vifs are ready. Perform the switch now depending on
1338          * reservations and driver capabilities.
1339          */
1340
1341         if (local->use_chanctx) {
1342                 if (n_vifs_switch > 0) {
1343                         err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
1344                         if (err)
1345                                 goto err;
1346                 }
1347
1348                 if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
1349                         err = ieee80211_chsw_switch_ctxs(local);
1350                         if (err)
1351                                 goto err;
1352                 }
1353         } else {
1354                 err = ieee80211_chsw_switch_hwconf(local, new_ctx);
1355                 if (err)
1356                         goto err;
1357         }
1358
1359         /*
1360          * Update all structures, values and pointers to point to new channel
1361          * context(s).
1362          */
1363
1364         i = 0;
1365         list_for_each_entry(ctx, &local->chanctx_list, list) {
1366                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1367                         continue;
1368
1369                 if (WARN_ON(!ctx->replace_ctx)) {
1370                         err = -EINVAL;
1371                         goto err;
1372                 }
1373
1374                 list_for_each_entry(sdata, &ctx->reserved_vifs,
1375                                     reserved_chanctx_list) {
1376                         u32 changed = 0;
1377
1378                         if (!ieee80211_vif_has_in_place_reservation(sdata))
1379                                 continue;
1380
1381                         rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
1382
1383                         if (sdata->vif.type == NL80211_IFTYPE_AP)
1384                                 __ieee80211_vif_copy_chanctx_to_vlans(sdata,
1385                                                                       false);
1386
1387                         ieee80211_check_fast_xmit_iface(sdata);
1388
1389                         sdata->radar_required = sdata->reserved_radar_required;
1390
1391                         if (sdata->vif.bss_conf.chandef.width !=
1392                             sdata->reserved_chandef.width)
1393                                 changed = BSS_CHANGED_BANDWIDTH;
1394
1395                         ieee80211_vif_update_chandef(sdata, &sdata->reserved_chandef);
1396                         if (changed)
1397                                 ieee80211_bss_info_change_notify(sdata,
1398                                                                  changed);
1399
1400                         ieee80211_recalc_txpower(sdata, false);
1401                 }
1402
1403                 ieee80211_recalc_chanctx_chantype(local, ctx);
1404                 ieee80211_recalc_smps_chanctx(local, ctx);
1405                 ieee80211_recalc_radar_chanctx(local, ctx);
1406                 ieee80211_recalc_chanctx_min_def(local, ctx);
1407
1408                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1409                                          reserved_chanctx_list) {
1410                         if (ieee80211_vif_get_chanctx(sdata) != ctx)
1411                                 continue;
1412
1413                         list_del(&sdata->reserved_chanctx_list);
1414                         list_move(&sdata->assigned_chanctx_list,
1415                                   &ctx->assigned_vifs);
1416                         sdata->reserved_chanctx = NULL;
1417
1418                         ieee80211_vif_chanctx_reservation_complete(sdata);
1419                 }
1420
1421                 /*
1422                  * This context might have been a dependency for an already
1423                  * ready re-assign reservation interface that was deferred. Do
1424                  * not propagate error to the caller though. The in-place
1425                  * reservation for originally requested interface has already
1426                  * succeeded at this point.
1427                  */
1428                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1429                                          reserved_chanctx_list) {
1430                         if (WARN_ON(ieee80211_vif_has_in_place_reservation(
1431                                         sdata)))
1432                                 continue;
1433
1434                         if (WARN_ON(sdata->reserved_chanctx != ctx))
1435                                 continue;
1436
1437                         if (!sdata->reserved_ready)
1438                                 continue;
1439
1440                         if (ieee80211_vif_get_chanctx(sdata))
1441                                 err = ieee80211_vif_use_reserved_reassign(
1442                                                 sdata);
1443                         else
1444                                 err = ieee80211_vif_use_reserved_assign(sdata);
1445
1446                         if (err) {
1447                                 sdata_info(sdata,
1448                                            "failed to finalize (re-)assign reservation (err=%d)\n",
1449                                            err);
1450                                 ieee80211_vif_unreserve_chanctx(sdata);
1451                                 cfg80211_stop_iface(local->hw.wiphy,
1452                                                     &sdata->wdev,
1453                                                     GFP_KERNEL);
1454                         }
1455                 }
1456         }
1457
1458         /*
1459          * Finally free old contexts
1460          */
1461
1462         list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
1463                 if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
1464                         continue;
1465
1466                 ctx->replace_ctx->replace_ctx = NULL;
1467                 ctx->replace_ctx->replace_state =
1468                                 IEEE80211_CHANCTX_REPLACE_NONE;
1469
1470                 list_del_rcu(&ctx->list);
1471                 kfree_rcu(ctx, rcu_head);
1472         }
1473
1474         return 0;
1475
1476 err:
1477         list_for_each_entry(ctx, &local->chanctx_list, list) {
1478                 if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
1479                         continue;
1480
1481                 list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1482                                          reserved_chanctx_list) {
1483                         ieee80211_vif_unreserve_chanctx(sdata);
1484                         ieee80211_vif_chanctx_reservation_complete(sdata);
1485                 }
1486         }
1487
1488         return err;
1489 }
1490
1491 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1492 {
1493         struct ieee80211_local *local = sdata->local;
1494         struct ieee80211_chanctx_conf *conf;
1495         struct ieee80211_chanctx *ctx;
1496         bool use_reserved_switch = false;
1497
1498         lockdep_assert_held(&local->chanctx_mtx);
1499
1500         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1501                                          lockdep_is_held(&local->chanctx_mtx));
1502         if (!conf)
1503                 return;
1504
1505         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1506
1507         if (sdata->reserved_chanctx) {
1508                 if (sdata->reserved_chanctx->replace_state ==
1509                     IEEE80211_CHANCTX_REPLACES_OTHER &&
1510                     ieee80211_chanctx_num_reserved(local,
1511                                                    sdata->reserved_chanctx) > 1)
1512                         use_reserved_switch = true;
1513
1514                 ieee80211_vif_unreserve_chanctx(sdata);
1515         }
1516
1517         ieee80211_assign_vif_chanctx(sdata, NULL);
1518         if (ieee80211_chanctx_refcount(local, ctx) == 0)
1519                 ieee80211_free_chanctx(local, ctx);
1520
1521         sdata->radar_required = false;
1522
1523         /* Unreserving may ready an in-place reservation. */
1524         if (use_reserved_switch)
1525                 ieee80211_vif_use_reserved_switch(local);
1526 }
1527
1528 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
1529                               const struct cfg80211_chan_def *chandef,
1530                               enum ieee80211_chanctx_mode mode)
1531 {
1532         struct ieee80211_local *local = sdata->local;
1533         struct ieee80211_chanctx *ctx;
1534         u8 radar_detect_width = 0;
1535         int ret;
1536
1537         lockdep_assert_held(&local->mtx);
1538
1539         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1540
1541         mutex_lock(&local->chanctx_mtx);
1542
1543         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1544                                             chandef,
1545                                             sdata->wdev.iftype);
1546         if (ret < 0)
1547                 goto out;
1548         if (ret > 0)
1549                 radar_detect_width = BIT(chandef->width);
1550
1551         sdata->radar_required = ret;
1552
1553         ret = ieee80211_check_combinations(sdata, chandef, mode,
1554                                            radar_detect_width);
1555         if (ret < 0)
1556                 goto out;
1557
1558         __ieee80211_vif_release_channel(sdata);
1559
1560         ctx = ieee80211_find_chanctx(local, chandef, mode);
1561         if (!ctx)
1562                 ctx = ieee80211_new_chanctx(local, chandef, mode);
1563         if (IS_ERR(ctx)) {
1564                 ret = PTR_ERR(ctx);
1565                 goto out;
1566         }
1567
1568         ieee80211_vif_update_chandef(sdata, chandef);
1569
1570         ret = ieee80211_assign_vif_chanctx(sdata, ctx);
1571         if (ret) {
1572                 /* if assign fails refcount stays the same */
1573                 if (ieee80211_chanctx_refcount(local, ctx) == 0)
1574                         ieee80211_free_chanctx(local, ctx);
1575                 goto out;
1576         }
1577
1578         ieee80211_recalc_smps_chanctx(local, ctx);
1579         ieee80211_recalc_radar_chanctx(local, ctx);
1580  out:
1581         if (ret)
1582                 sdata->radar_required = false;
1583
1584         mutex_unlock(&local->chanctx_mtx);
1585         return ret;
1586 }
1587
1588 int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
1589 {
1590         struct ieee80211_local *local = sdata->local;
1591         struct ieee80211_chanctx *new_ctx;
1592         struct ieee80211_chanctx *old_ctx;
1593         int err;
1594
1595         lockdep_assert_held(&local->mtx);
1596         lockdep_assert_held(&local->chanctx_mtx);
1597
1598         new_ctx = sdata->reserved_chanctx;
1599         old_ctx = ieee80211_vif_get_chanctx(sdata);
1600
1601         if (WARN_ON(!new_ctx))
1602                 return -EINVAL;
1603
1604         if (WARN_ON(new_ctx->replace_state ==
1605                     IEEE80211_CHANCTX_WILL_BE_REPLACED))
1606                 return -EINVAL;
1607
1608         if (WARN_ON(sdata->reserved_ready))
1609                 return -EINVAL;
1610
1611         sdata->reserved_ready = true;
1612
1613         if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
1614                 if (old_ctx)
1615                         err = ieee80211_vif_use_reserved_reassign(sdata);
1616                 else
1617                         err = ieee80211_vif_use_reserved_assign(sdata);
1618
1619                 if (err)
1620                         return err;
1621         }
1622
1623         /*
1624          * In-place reservation may need to be finalized now either if:
1625          *  a) sdata is taking part in the swapping itself and is the last one
1626          *  b) sdata has switched with a re-assign reservation to an existing
1627          *     context readying in-place switching of old_ctx
1628          *
1629          * In case of (b) do not propagate the error up because the requested
1630          * sdata already switched successfully. Just spill an extra warning.
1631          * The ieee80211_vif_use_reserved_switch() already stops all necessary
1632          * interfaces upon failure.
1633          */
1634         if ((old_ctx &&
1635              old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
1636             new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
1637                 err = ieee80211_vif_use_reserved_switch(local);
1638                 if (err && err != -EAGAIN) {
1639                         if (new_ctx->replace_state ==
1640                             IEEE80211_CHANCTX_REPLACES_OTHER)
1641                                 return err;
1642
1643                         wiphy_info(local->hw.wiphy,
1644                                    "depending in-place reservation failed (err=%d)\n",
1645                                    err);
1646                 }
1647         }
1648
1649         return 0;
1650 }
1651
1652 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
1653                                    const struct cfg80211_chan_def *chandef,
1654                                    u32 *changed)
1655 {
1656         struct ieee80211_local *local = sdata->local;
1657         struct ieee80211_chanctx_conf *conf;
1658         struct ieee80211_chanctx *ctx;
1659         const struct cfg80211_chan_def *compat;
1660         int ret;
1661
1662         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
1663                                      IEEE80211_CHAN_DISABLED))
1664                 return -EINVAL;
1665
1666         mutex_lock(&local->chanctx_mtx);
1667         if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
1668                 ret = 0;
1669                 goto out;
1670         }
1671
1672         if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
1673             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
1674                 ret = -EINVAL;
1675                 goto out;
1676         }
1677
1678         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1679                                          lockdep_is_held(&local->chanctx_mtx));
1680         if (!conf) {
1681                 ret = -EINVAL;
1682                 goto out;
1683         }
1684
1685         ctx = container_of(conf, struct ieee80211_chanctx, conf);
1686
1687         compat = cfg80211_chandef_compatible(&conf->def, chandef);
1688         if (!compat) {
1689                 ret = -EINVAL;
1690                 goto out;
1691         }
1692
1693         switch (ctx->replace_state) {
1694         case IEEE80211_CHANCTX_REPLACE_NONE:
1695                 if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
1696                         ret = -EBUSY;
1697                         goto out;
1698                 }
1699                 break;
1700         case IEEE80211_CHANCTX_WILL_BE_REPLACED:
1701                 /* TODO: Perhaps the bandwidth change could be treated as a
1702                  * reservation itself? */
1703                 ret = -EBUSY;
1704                 goto out;
1705         case IEEE80211_CHANCTX_REPLACES_OTHER:
1706                 /* channel context that is going to replace another channel
1707                  * context doesn't really exist and shouldn't be assigned
1708                  * anywhere yet */
1709                 WARN_ON(1);
1710                 break;
1711         }
1712
1713         ieee80211_vif_update_chandef(sdata, chandef);
1714
1715         ieee80211_recalc_chanctx_chantype(local, ctx);
1716
1717         *changed |= BSS_CHANGED_BANDWIDTH;
1718         ret = 0;
1719  out:
1720         mutex_unlock(&local->chanctx_mtx);
1721         return ret;
1722 }
1723
1724 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
1725 {
1726         WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
1727
1728         lockdep_assert_held(&sdata->local->mtx);
1729
1730         mutex_lock(&sdata->local->chanctx_mtx);
1731         __ieee80211_vif_release_channel(sdata);
1732         mutex_unlock(&sdata->local->chanctx_mtx);
1733 }
1734
1735 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
1736 {
1737         struct ieee80211_local *local = sdata->local;
1738         struct ieee80211_sub_if_data *ap;
1739         struct ieee80211_chanctx_conf *conf;
1740
1741         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
1742                 return;
1743
1744         ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
1745
1746         mutex_lock(&local->chanctx_mtx);
1747
1748         conf = rcu_dereference_protected(ap->vif.chanctx_conf,
1749                                          lockdep_is_held(&local->chanctx_mtx));
1750         rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
1751         mutex_unlock(&local->chanctx_mtx);
1752 }
1753
1754 void ieee80211_iter_chan_contexts_atomic(
1755         struct ieee80211_hw *hw,
1756         void (*iter)(struct ieee80211_hw *hw,
1757                      struct ieee80211_chanctx_conf *chanctx_conf,
1758                      void *data),
1759         void *iter_data)
1760 {
1761         struct ieee80211_local *local = hw_to_local(hw);
1762         struct ieee80211_chanctx *ctx;
1763
1764         rcu_read_lock();
1765         list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1766                 if (ctx->driver_present)
1767                         iter(hw, &ctx->conf, iter_data);
1768         rcu_read_unlock();
1769 }
1770 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);